Environmentally Friendly Vehicle Noise. 9 th Informal Group Meeting on Environmentally Friendly Vehicle (EFV) - Noise

Transcription

1 Environmentally Friendly Vehicle Noise 1

2 Overview Purpose & Method Of Evaluation Interior noise of the vehicle? Methods to present the pass-by data Tyre/Road contribution Quiet vehicles. 2

3 Background Informal Group working paper no. EFV-07-05, 05 EFV was presented in GRPE EFV group, now it is presented in GRB group for input from Noise experts. These summarizes Noise Regulations followed in various countries and attempted to rank in terms of Noise levels. Based on Hybrid and Electric vehicles minimum noise level to be defined. 3

4 Purpose Information to the customer about the noise performance of the vehicle so that he/she can make an intelligent choice for purchase of the vehicle. The vehicular noise can cause disturbance and inconvenience to the road user, pedestrian as well as near by residents. Environmental noise, caused by traffic is considered to be a significant local environmental problem in world. It is estimated that millions of people suffer from noise levels that scientists and health experts consider unacceptable. This is evaluated through pass-by noise regulation ECE-R51 3

5 Should we consider Internal Noise as one of the factors for assessing Environmental Performance of the vehicle? 4

6 Effect of increase in volume of vehicles. For example considering 20 vehicles of same class having 66 db(a) 79 db(a) Data referred from TNO Report Environmental Calculated Noise Lp = 10* Log(n*(10 (Li/10) )) 5

7 How should we assess vehicles? Type 1 Single value Vehicle under consideration Min* db(a) 74 db(a) Should show the range of noise levels in M1 class of vehicle with maximum value as the noise limit. Actual values can be represented easily. Would require continuous up gradation of the range at periodic intervals. * Minimum value could be quiet vehicle expected through future technology. 6

8 Type of representation of pass-by values Type 2 Ranking es No of vehicl db(a) Vehicles are classified in different groups of 2 dba each. Difficult to represent actual values of a particular model 7

9 Typical representation through Type 2 Scatter diagram (sample data) less than 66 Data taken up to 74 db(a) db(a) Numb ber of Vehicles Type db(a) Num mber of Vehicl les Almost 40% vehicles will just fall in 2 classes. May be difficult for the customer to know the fine differences between vehicles. 8

10 Traffic Noise Reduction Potential Source Paper on Road Traffic Noise; VDA Technical congress 2005, Ingolstadt, Germany 9

11 Pass-by noise reduction in last 3 decades 10

12 Tyre/Road surface contribution.. Even a good vehicle can be termed as bad because of road surface which is not in control of vehicle designer. Source p09 htm Reducing noise is more than just making silent engines and tyres. It is also about silent pavements, or, how innovative infrastructure can help improve traffic conditions. New techniques mean road surfaces can help reduce the total sound output by up to 10 decibels. 11

13 Quiet vehicles Silent cars are electric and hybrid vehicles that do not emit the noises caused by combustion engines. While they constitute a key contribution to reducing carbon emissions and rising consumer awareness about climate change, they may also prove to be an additional risk for pedestrians and other road users. Source In order to address the risk for pedestrian, the minimum sound level required needs to be established. This will also enable to fix the minimum i levell for EFV. 12

14 Open Questions Should we consider Interior noise for assessment? What method can be adapted for Noise Assessment? How to consider other factors contributing to Noise while assessment? 3

15 Open for Discussion 13

16 Thank You 13